This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by da Silva Ferreira, M. E.
Right arrow Articles by Goldman, G. H.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by da Silva Ferreira, M. E.
Right arrow Articles by Goldman, G. H.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, November 2004, p. 4405-4413, Vol. 48, No. 11
0066-4804/04/$08.00+0     DOI: 10.1128/AAC.48.11.4405-4413.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

In Vitro Evolution of Itraconazole Resistance in Aspergillus fumigatus Involves Multiple Mechanisms of Resistance

Márcia Eliana da Silva Ferreira,1 José Luiz Capellaro,1 Everaldo dos Reis Marques,1 Iran Malavazi,1 David Perlin,2 Steven Park,2 James B. Anderson,3 Arnaldo L. Colombo,4 Beth A. Arthington-Skaggs,5 Maria Helena S. Goldman,6 and Gustavo H. Goldman1*

Faculdade de Ciências Farmacêuticas de Ribeirão Preto,1 Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo,6 Laboratório Especial de Micologia, Universidade Federal de São Paulo, São Paulo, Brazil,4 Public Health Research Institute, Newark, New Jersey,2 Department of Botany, University of Toronto, Mississauga, Ontario, Canada,4 Mycotic Diseases Branch, Division of Bacterial and Mycotic Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia5

Received 15 January 2004/ Returned for modification 26 February 2004/ Accepted 5 July 2004

We investigated the evolution of resistance to the antifungal drug itraconazole in replicate populations of Aspergillus fumigatus that were founded from a strain with a genotype of sensitivity to a single drug and then propagated under uniform conditions. For each population, conidia were serially transferred 10 times to agar medium either with or without itraconazole. After 10 transfers in medium supplemented with itraconazole, 10 itraconazole-resistant mutant strains were isolated from two populations. These mutant strains had different growth rates and different levels of itraconazole resistance. Analysis of the ergosterol contents of these mutants showed that they accumulate ergosterol when they are grown in the presence of itraconazole. The replacement of the CYP51A gene of the wild-type strain changed the susceptibility pattern of this strain to one of itraconazole resistance only when CYP51A genes with N22D and M220I mutations were used as selectable marker genes. Real-time quantitative reverse transcription-PCR was used to assess the levels of expression of the Afumdr1, Afumdr2, Afumdr3, Afumdr4, AtrF transporter, CYP51A, and CYP51B genes in these mutant strains. Most mutants showed either constitutive high-level expression or induction upon exposure of Afumdr3, Afumdr4, and AtrF to itraconazole. Our results suggest that overexpression of drug efflux pumps and/or selection of drug target site mutations are at least partially responsible for itraconazole resistance and could be considered mechanisms for the emergence of clinical resistance to this drug.

* Corresponding author. Mailing address: Departamento de Ciências Farmacêuticas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av. do Café S/N, CEP 14040-903, Ribeirão Preto, São Paulo, Brazil. Phone: 0055-016-6024280. Fax: 0055-016-6331092. E-mail: ggoldman{at}usp.br.

Antimicrobial Agents and Chemotherapy, November 2004, p. 4405-4413, Vol. 48, No. 11
0066-4804/04/$08.00+0     DOI: 10.1128/AAC.48.11.4405-4413.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Sionov, E., Chang, Y. C., Garraffo, H. M., Kwon-Chung, K. J. (2009). Heteroresistance to Fluconazole in Cryptococcus neoformans Is Intrinsic and Associated with Virulence. Antimicrob. Agents Chemother. 53: 2804-2815 [Abstract] [Full Text]  
  • Snelders, E., Huis in 't Veld, R. A. G., Rijs, A. J. M. M., Kema, G. H. J., Melchers, W. J. G., Verweij, P. E. (2009). Possible Environmental Origin of Resistance of Aspergillus fumigatus to Medical Triazoles. Appl. Environ. Microbiol. 75: 4053-4057 [Abstract] [Full Text]  
  • Beernaert, L. A., Pasmans, F., Van Waeyenberghe, L., Dorrestein, G. M., Verstappen, F., Vercammen, F., Haesebrouck, F., Martel, A. (2009). Avian Aspergillus fumigatus Strains Resistant to both Itraconazole and Voriconazole. Antimicrob. Agents Chemother. 53: 2199-2201 [Abstract] [Full Text]  
  • Cannon, R. D., Lamping, E., Holmes, A. R., Niimi, K., Baret, P. V., Keniya, M. V., Tanabe, K., Niimi, M., Goffeau, A., Monk, B. C. (2009). Efflux-Mediated Antifungal Drug Resistance. Clin. Microbiol. Rev. 22: 291-321 [Abstract] [Full Text]  
  • Arendrup, M. C., Perkhofer, S., Howard, S. J., Garcia-Effron, G., Vishukumar, A., Perlin, D., Lass-Florl, C. (2008). Establishing In Vitro-In Vivo Correlations for Aspergillus fumigatus: the Challenge of Azoles versus Echinocandins. Antimicrob. Agents Chemother. 52: 3504-3511 [Abstract] [Full Text]  
  • Cowen, L. E., Steinbach, W. J. (2008). Stress, Drugs, and Evolution: the Role of Cellular Signaling in Fungal Drug Resistance. Eukaryot Cell 7: 747-764 [Full Text]  
  • Garcia-Effron, G., Dilger, A., Alcazar-Fuoli, L., Park, S., Mellado, E., Perlin, D. S. (2008). Rapid Detection of Triazole Antifungal Resistance in Aspergillus fumigatus. J. Clin. Microbiol. 46: 1200-1206 [Abstract] [Full Text]  
  • Mellado, E., Garcia-Effron, G., Alcazar-Fuoli, L., Melchers, W. J. G., Verweij, P. E., Cuenca-Estrella, M., Rodriguez-Tudela, J. L. (2007). A New Aspergillus fumigatus Resistance Mechanism Conferring In Vitro Cross-Resistance to Azole Antifungals Involves a Combination of cyp51A Alterations. Antimicrob. Agents Chemother. 51: 1897-1904 [Abstract] [Full Text]  
  • Osborne, C. S., Leitner, I., Hofbauer, B., Fielding, C. A., Favre, B., Ryder, N. S. (2006). Biological, Biochemical, and Molecular Characterization of a New Clinical Trichophyton rubrum Isolate Resistant to Terbinafine.. Antimicrob. Agents Chemother. 50: 2234-2236 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»